In the field of plumbing fixtures and the like, it is well known to provide pop-up drain fittings which selectively seal drain fittings for tubs, sinks, and the like. Generally speaking, such pop-up drain fittings are disposed within a cylindrical drain body, and are secured to the drain body by means of a spider extending diametrically across the lower opening of the drain body. More specifically, the pop-up drain fitting generally includes a central post having a lower threaded end which is received in a medially disposed threaded hole in the spider of the drain body.
It is common practice to employ the pop-up drain fitting by depressing the upper cover of the mechanism to cause a rubber seal to close the upper opening of the drain body. To release this valve, it is necessary only to depress a button on the upper portion of the fitting, or to depress a particular side edge portion of the cover to effect release of the mechanism and opening of the drain.
However, recent experience has shown that it is also common practice for vandals and others to completely remove the pop-up mechanism from drain by unthreading the mechanism from the spider. There is no pop-up drain mechanism known in the prior art which is designed to resist or withstand such tampering or vandalism.